Preeclampsia is a major contributor to maternal and perinatal morbidity and mortality. Prevention and treatment require an understanding of both pathophysiology and clinical characterization. The Data and Clinical Core will centralize recruitment, baseline data collection,, data management, and statistical consultation for clinical projects within the Program Project. Specifically, these activities will entail recruiting, over a four-year period, an estimated 1700 nulliparous pregnant women without prior evidence of coronary hear5t disease risk and with singleton gestations from Magee-Womens Hospital in Pittsburgh. Baseline clinical and laboratory data will be obtained at or prior to 16 weeks gestation and additional biologic samples will be collected at several time points throughout the pregnancy. Furthermore, 200 preeclamptic 200 normotensive and 200 intrauterine growth restricted (IUGR) pregnancies will be studied cross-sectionally at labor and delivery. Finally, 140 women will be recruited at 6-12 months post-partum. In all cases, the Core staff will be responsible for recruitment, data collection (except for special tests described in specific projects), and quality assurance. The Core will also characterize preeclamptic and IUGR women using a strict set of diagnostic criteria and a jury of clinical experts. Data will be organized and maintained using the expertise within the Department of Epidemiology. Statistical consultation will be provided for all projects in an ongoing fashion. The Core builds on extraordinary current success. To date, in the current Program Project, we have enrolled over 23000 women over about four years and will identify almost 400 preeclamptic women. Therefore, we are confident in our ability to take these activities forward into the future.